Overview of some basic requirements for a reentry prediction service for civil protection applications

Even though the overall risk represented by the uncontrolled reentry of artificial space objects is still extremely low compared to many other hazards faced every day by individuals and societies, some of these events are receiving a growing attention from the media and the public, often involving the national authorities in charge of civil protection. When political authorities, government agencies, journalists, the public, and the judiciary are involved in the process, reentry predictions are no longer just a scientific task restricted to the technical community. This makes the assignment much more complicated and sensitive, further worsened by the fact that reentry predictions still remain affected by considerable and unavoidable uncertainties, making impossible, in most of the cases, the identification of a specific reentry time and location even in the last few hours. This paper reviews the challenges faced in such situations, presenting the solutions devised in Italy, in particular during the last twenty years, to meet the specific requirements of the national civil protection system, and address the legal and liability aspects.